Mobile or wireless devices are increasingly becoming used for a variety of tasks. These tasks may require different hardware and configurations in order to run more efficiently, and in some cases the different hardware is comprised of various processors having specialized tasks. For example, one processor may be used to run user applications, while a second may be used for control of the radio and voice path on the mobile device.
In multi-processor environments where the audio path may be generated from either of an application processor (controller processor) or a radio processor, a complex series of tasks need to occur in order to produce the audio output at one of a plurality of audio outputs. This is further complicated if additional hardware such as an audio chip, referred to herein as a Melody chip, is added. With the above dual processor configuration, the Melody chip is controlled by the application processor.
The audio source with the above configuration can be either the Melody chip or a voice codec. In this case, the analog output from the Melody chip needs to be amplified before being sent through a multiplexer to choose between the Melody chip and the voice codec chip output. Once multiplexed, the audio can go to the output, such as a speaker, headset, handset, Bluetooth™ or any other such audio output. This requires considerable hardware and coordination in the output of the audio.